I have two new, multiple-cavity molds, a Lee and MP mold. The Lee is aluminum and the MP is brass.
I’ve ready many like to clean the molds with white gas (Coleman fuel) or mineral spirits... or boil with dish soap, which leaves some kind of protective coating/oxide on the molds.
If going the boiling route do you put the whole thing in the pot? Or do you take the spruce plate, screws, etc. off till you get it down to just the mold (or as close as you can if there are press-fit parts)?